The latest venture by Russian billionaire Yuri Milner in his quest to find alien life is set to be unveiled by Stephen Hawking on Tuesday.

Starshot is the latest project in Milner’s decade-long search for extraterrestrial intelligence (SETI), which he set up in July 2015, under the banner Breakthrough Initiatives.

Milner, whose net worth is estimated to be $2.9 billion by Forbes, has pledged $100 million towards Breakthrough Initiatives, making it the biggest hunt for alien life ever staged.

“In the last five years, we have discovered that planets in the habitable zone of stars are common,” Breakthrough Initiatives’ website states. “Based on the numbers discovered so far, there are estimated to be billions more in our galaxy alone. And there are hundreds of billions of galaxies in the visible Universe.

“Yet we are still in the dark about life. Are we really alone? Or are there others out there? It’s one of the biggest questions. And only science can answer it.”

Little is known about the Starshot project, with a media advisory describing it simply as a “new space exploration initiative.” The announcement will take place at One World Observatory in New York at 12pm EDT, a day that also marks the 55th anniversary of the first ever human space flight by Russian cosmonaut Yuri Gagarin.

Hawking has previously warned of the dangers posed by intelligent extraterrestrials, saying that an advanced alien race could potentially wipe out humanity. In 2010, Hawking said nomadic aliens may look to “conquer and colonize” any civilization they came across.

At the launch of the Breakthrough initiative last year, Hawking said:” I am here today because I believe the Breakthrough initiatives are incredibly important.

“It’s time to search for life beyond Earth. The Breakthrough initiatives are making that commitment. We are alive. We are intelligent. We must know.”

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